Magnesian andesite in the western Aleutian Komandorsky region: Implications for slab melting and processes in the mantle wedge

  title={Magnesian andesite in the western Aleutian Komandorsky region: Implications for slab melting and processes in the mantle wedge},
  author={Gene Yogodzinski and Robert W. Kay and Oleg N. Volynets and A. V. Koloskov and Suzanne Kay},
  journal={Geological Society of America Bulletin},
The role of the subducting lithospheric slab in the genesis of mantle-derived (primitive) magmas is investigated through a study of volcanic rocks formed in the tectonically strike-slip–dominated western Aleutian arc. Two types of chemically and petrologically distinctive primitive andesites have been found among the Miocene–late Pleistocene–age volcanic rocks in the western Aleutians. These are termed the “Adak-type” and “Piip-type” magnesian andesites. Trace element and isotopic… 

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